Note: Descriptions are shown in the official language in which they were submitted.
CA 02800183 2012-11-21
WO 2011/149460 PCT/US2010/036296
1
METHOD AND SYSTEM OF RENDERING WELL LOG VALUES
BACKGROUND
[0001] In the continuing advancements in recovery of natural resources, such
as oil and
natural gas trapped in underground formations, many companies use computer
systems
to help synthesize and understand data gathered regarding a well. Such
synthesis
assists geologists in making determinations such as the best reservoir
extraction
technique, and best location at which to extract the natural resources.
[0002] In many cases, data regarding a well, or multiple wells, are displayed
on the
display device of a computer system in such a way as to not only show the
three
dimensional direction of the well (projected in the two dimensions of the
display device),
but also in such a way that changes in the field of view are animated to
simulate a
"smoothly" changing scene (e.g., greater than about 20 frames per second) in
transitions
from one field of view to the next. However, the number of memory objects
stored in
display memory used to render even a single set of log data is enormous,
stretching the
limits of graphics capabilities of currently available graphics systems. The
problems are
exacerbated when a user desires to show in the same frame portions of well log
values of
multiple types or from multiple wells.
[0003] Thus, any advance in the synthesis and visualization of data for one or
more
wells would provide a competitive advantage in the market place.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] For a detailed description of exemplary embodiments, reference will now
be
made to the accompanying drawings in which:
[0005] Figure 1 shows a perspective view an illustrative trajectory of a
welibore;
[0006] Figure 2 shows a portion of a well log in accordance with at least some
embodiments;
[0007] Figure 3 shows a computer system in accordance with at least some
embodiments;
[0008] Figure 4 shows a software environment in accordance with at least some
embodiments;
CA 02800183 2012-11-21
WO 2011/149460 PCT/US2010/036296
2
[0009] Figure 5 shows a constructing a curve of well log values using
underlying
geometry;
[0010] Figure 6 shows a series of panels, as well as a first set of well log
values and a
curve program, in accordance with at least some embodiments;
[0011] Figure 7 shows a series of panels showing a trajectory of a wellbore in
accordance with at least some embodiments;
[0012] Figure 8 shows a panel with a curve in accordance with at least some
embodiments;
[0013] Figure 9 shows a panel with multiple curves rendered therein in
accordance with
at least some embodiments;
[0014] Figure 10 shows a panel with multiple curves rendered therein in
accordance
with at least some embodiments; and
[0015] Figure 11 shows a method in accordance with at least some embodiments.
NOTATION AND NOMENCLATURE
[0016] Certain terms are used throughout the following description and claims
to refer to
particular system components. As one skilled in the art will appreciate,
software
companies may refer to a component by different names. This document does not
intend
to distinguish between components that differ in name but not function. In the
following
discussion and in the claims, the terms "including" and "comprising" are used
in an open-
ended fashion, and thus should be interpreted to mean "including, but not
limited to...."
Also, the term "couple" or "couples" is intended to mean either an indirect or
direct
connection. Thus, if a first device couples to a second device, that
connection may be
through a direct connection or through an indirect connection via other
devices and
connections.
[0017] "Wellbore" shall mean a hole drilled into the Earth's crust used
directly or
indirectly for the exploration or extraction of natural resources, such as
oil, natural gas or
water.
[0018] "Panel" shall mean a surface defined by vertices. A panel defines only
a location,
and does not define the pattern, color and/or illumination of pixels within
the panel.
Consider, as an example, a panel in the form of a rectangular face of a cubic
volume.
CA 02800183 2012-11-21
WO 2011/149460 PCT/US2010/036296
3
The panel defines only the rectangular face, and not the pattern, color and/or
illumination
of pixels within the panel.
[0019] "Well log values" shall mean a plurality of values of an attribute of
one or more
earth formation penetrated by a wellbore.
DETAILED DESCRIPTION
[0020] The following discussion is directed to various embodiments of the
invention.
Although one or more of these embodiments may be preferred, the embodiments
disclosed should not be interpreted, or otherwise used, as limiting the scope
of the
disclosure, including the claims. In addition, one skilled in the art will
understand that the
following description has broad application, and the discussion of any
embodiment is
meant only to be exemplary of that embodiment, and not intended to intimate
that the
scope of the disclosure, including the claims, is limited to that embodiment.
[0021] The various embodiments are directed to mechanisms to display or
"visualize"
well log values associated with wellbores that penetrate Earth formations. For
ease of
description, the various embodiments are discussed in terms of a single
wellbore
penetrating one or more Earth formations. The single wellbore has associated
therewith
at least one set of well log values, where each set of well log values
represents a physical
parameter associated with the formation penetrated by the wellbore or the
wellbore itself.
However, the various embodiments may also be used to display well log values
from
multiple wellbores, and thus the nature of the description shall not be read
as a limitation
as to the applicability of the various embodiments.
[0022] Figure 1 illustrates a wellbore 10, which wellbore 10 may be drilled
into the Earth
for purposes of exploration and/or extraction of natural resources, such as
hydrocarbons
(e.g., oil and gas) and water. The balance of this description assumes
wellbore 10 is
drilled for purposes of exploration and/or extraction of hydrocarbons, but
such assumption
shall not be read to limit the techniques described only to hydrocarbon
exploration.
Moreover, it is noted that the wellbore 10 need not itself be a hydrocarbon
producing
wellbore. In some case, wellbores are drilled for exploratory purposes, or for
other
purposes that aid in the extraction of hydrocarbons, such as injection wells.
Illustrative
wellbore 10 has a trajectory (i.e., a three-dimensional path through the
underlying Earth
formation(s)) that can be considered to start at the surface 12 of the Earth.
Initially, the
CA 02800183 2012-11-21
WO 2011/149460 PCT/US2010/036296
4
illustrative wellbore 10 is substantially vertical, as illustrated by portion
14. After extending
some distance into the Earth, the illustrative wellbore 10 turns toward the
East and the
downward slope decreases, as indicated by portion 16. Thereafter, the downward
slope
of the illustrative wellbore 10 increases again, as illustrated by portion 18.
The slope of
the illustrative wellbore 10 then decreases to the point where the wellbore 10
is
substantially horizontal, as illustrated by portion 20. While illustrative
wellbore 10 has no
trajectory change from the East direction, the wellbore 10 may likewise change
trajectory
in any three-dimensional direction.
[0023] At various times during creation of the wellbore 10, data regarding
physical
parameters of the one or more formations penetrated by the wellbore may be
gathered.
For example, the drill string that creates wellbore 10 may include measuring-
while-drilling
or logging-while-drilling devices that read physical parameters of the
formations as the
drill bit creates the wellbore 10. Further, at various times during the
drilling process the
drill string may be removed from the wellbore 10, and a wireline logging tool
run therein,
where the wireline logging tool gathers data regarding the physical parameters
of the
formations penetrated by the wellbore 10. Further still, after drilling is
complete and
wellbore 10 is cased, additional logging tools may be run in the wellbore 10.
[0024] The type of data sets created by the data gathering processes also
varies. For
example, the various tools may measure physical parameters of the formations
as a
function of depth, such as porosity, electrical resistivity (reciprocal of
conductivity),
density, natural gamma production, responses to neutron interrogation, and
capture
cross-section. Moreover, the physical parameters of some data sets may provide
information regarding lithology of the Earth formations. Further still, the
physical
parameters of some data sets may provide information regarding properties of
the
wellbore itself as a function of depth, such as casing thickness, cement
thickness, and
casing bond impedance.
[0025] Regardless of the precise nature of the parameters that a particular
data set
contains, in order to be useful the data sets are presented to geologist or
other interested
party by way of display device of a computer system in a form known as a log.
Figure 2
shows an illustrative view of a portion of a log for purposes of discussion.
In particular, log
200 comprises curve 202, which curve 202 shows the value of a parameter based
on the
depth D within a wellbore, with depth D illustratively increasing downward.
For example,
CA 02800183 2012-11-21
WO 2011/149460 PCT/US2010/036296
for increasing values of the parameter, the curve 202 shifts to the left
(e.g., portion 204),
and for decreasing values of the parameter, the curve 202 shifts to the right
(e.g.,
portion 206). Taking the parameter of the log 200 to be measured porosity of
the
formation, the porosity of the formation is higher at the depth associated
with portion 204,
and lower at the depth associated with portion 206. From the view point of
Figure 2, or
alternatively stated at the magnification of illustrative Figure 2, the curve
202 appears to
be somewhat smoothly varying. However, the curve 202 is constructed based on
discrete
points of underlying well log values, with straight lines extending between
each discrete
point, as illustrated by the magnified region 208. Thus, the curve 202 as
illustrated is
piecewise linear.
[0026] In order to describe the interactions between various processors of a
computer
system to implement the display of curves in accordance with the various
embodiments,
the specification now turns to an illustrative computer system. Figure 3
illustrates a
computer system 300 in accordance with at least some embodiments. In
particular,
computer system 300 comprises a main processor 310 coupled to a main memory
array
312, and various other peripheral computer system components, through
integrated host
bridge 314. Computer system 300 may implement multiple main processors 310.
The
main processor 310 couples to the host bridge 314 by way of a host bus 316, or
the host
bridge 314 may be integrated into the main processor 310. Thus, the computer
system 300 may implement other bus configurations or bus-bridges in addition
to, or in
place of, those shown in Figure 3.
[0027] The main memory 312 couples to the host bridge 314 through a memory
bus 318. Thus, the host bridge 314 comprises a memory control unit that
controls
transactions to the main memory 312 by asserting control signals for memory
accesses.
In other embodiments, the main processor 310 directly implements a memory
control unit,
and the main memory 312 may couple directly to the main processor 310. The
main
memory 312 functions as the working memory for the main processor 310 and
comprises
a memory device or array of memory devices in which programs, instructions and
data
are stored. The main memory 312 may comprise any suitable type of memory such
as
dynamic random access memory (DRAM) or any of the various types of DRAM
devices
such as synchronous DRAM (SDRAM), extended data output DRAM (EDODRAM), or
Rambus DRAM (RDRAM). The main memory 312 is an example of a non-transitory
CA 02800183 2012-11-21
WO 2011/149460 PCT/US2010/036296
6
computer-readable medium storing programs and instructions, and other examples
are
disk drives and flash memory devices.
[0028] The illustrative computer system 300 also comprises a second bridge 328
that
bridges the primary expansion bus 326 to various secondary expansion buses,
such as a
low pin count (LPC) bus 330 and peripheral components interconnect (PCI) bus
332.
Various other secondary expansion buses may be supported by the bridge device
328.
However, computer system 300 is not limited to any particular chip set
manufacturer, and
thus bridge devices and expansion bus protocols from any of a variety of
manufacturers
may be equivalently used.
[0029] Firmware hub 336 couples to the bridge device 728 by way of the LPC bus
332.
The firmware hub 334 comprises read-only memory (ROM) which contains software
programs executable by the main processor 710. The software programs comprise
programs executed during and just after power on self tests (POST) procedures
as well
as memory reference code. The POST procedures and memory reference code
perform
various functions within the computer system before control of the computer
system is
turned over to the operating system.
[0030] The computer system 300 further comprises a network interface card
(NIC) 338
illustratively coupled to the PCI bus 332. The NIC 338 acts as to couple the
computer
system 300 to a communication network, such the Internet.
[0031] Still referring to Figure 3, computer system 300 may further comprise a
super
input/output (I/O) controller 340 coupled to the bridge 328 by way of the LPC
bus 330.
The Super I/O controller 340 controls many computer system functions, for
example
interfacing with various input and output devices such as a disk drive 334,
keyboard 342,
a pointing device 344 (e.g., mouse), game controller 346, and various serial
ports. The
super I/O controller 340 is often referred to as "super" because of the many
I/O functions it
performs.
[0032] The computer system 300 further comprises a graphics processing unit
(GPU)
350 coupled to the host bridge 314 by way of bus 352, such as a PCI Express
(PCI-E)
bus or Advanced Graphics Processing (AGP) bus. Other bus systems, including
after-
developed bus systems, may be equivalently used. Moreover, the graphics
processing
unit 350 may alternatively couple to the primary expansion bus 326, or one of
the
secondary expansion buses (e.g., PCI bus 332).
CA 02800183 2012-11-21
WO 2011/149460 PCT/US2010/036296
7
[0033] The graphics processing unit 350 couples to a display device 354 which
may
comprise any suitable electronic display device upon which any image or text
can be
displayed. The graphics processing unit 350 comprises one or more onboard
processors
356, as well as onboard memory 358. The processor 356 performs graphics
processing,
as commanded by the main processor 310 (discussed more fully below). Moreover,
the
memory 358 may be significant, on the order of several hundred megabytes or
more.
Thus, once commanded by the main processor 310, the graphics processing unit
350
may perform significant calculations regarding graphics to be displayed on the
display
device, and ultimately display such graphics, without further input or
assistance of the
main processor 310.
[0034] While Figure 3 shows an illustrative hardware environment, Figure 4
shows an
illustrative software environment 400 within which the various embodiments may
operate.
At the base of the software environment 400 is an operating system 402, such
as a
WindowsTM operating system from Microsoft Corporation. Menu and interface
software
104 overlays operating system 102. Menu and interface software 104 are used to
provide
various menus and windows to facilitate interaction with the user, and to
obtain user input
and instructions. Menu and interface software 404 may comprise, for example,
WindowsTM, X Free 86TM, and/or MOTIFTM.
[0035] A basic graphics library 406 overlays menu and interface software 404.
Basic
graphics library 106 is an application programming interface (API) for
computer graphics.
The functions performed by basic graphics library 406 may comprise, for
example,
geometric and raster primitives, viewing and modeling transformations,
lighting and
shading, hidden surface removal, alpha blending (translucency), anti-aliasing,
texture
mapping, and atmospheric effects (fog, smoke, haze). A particularly useful
basic graphics
library 406 is OpenGLTM, marketed by Khronos Group of Beaverton, Oregon, and
particular OpenGLTM 2.0 and above. The OpenGLTM API is a multi-platform
industry
standard that is hardware, window, and operating system independent. OpenGLTM
is
designed to be callable from multiple programming languages, such as C, C++,
FORTRAN, Ada and Java.
[0036] Visual simulation graphics library 408 overlays the basic graphics
library 406.
Visual simulation graphics library 408 is an API for creating real-time, multi-
processed 3-D
visual simulation graphics applications. Visual simulation graphics library
408 provides
CA 02800183 2012-11-21
WO 2011/149460 PCT/US2010/036296
8
functions that bundle together graphics library state control functions such
as lighting,
materials, texture, and transparency. These functions track state and the
creation of
display lists that can be rendered later. A particularly useful visual
simulation graphics
library 408 is Open Scene GraphTM, which is also available from Khronos Group.
OpenSceneGraphTM supports the OpenGLTM graphics library discussed above. Open
Scene Graph TM operates in the same manner as OpenGL Performer TM, providing
programming tools written in C/C++ for a large variety of computer platforms.
[0037] A well log rendering program 410 of the various embodiments overlays
visual
simulation graphics library 408. Program 410 interfaces with, and utilizes the
functions
carried out by, the visual simulation graphics library 408, basic graphics
library 406, menu
and interface software 404, and operating system 402. In some embodiments
program
410 is written in an object oriented programming language (e.g., C++) to
enable the
creation and use of objects and object functionality.
[0038] Some or all of the software environment 400 may be stored on a long
term, non-
volatile storage device within computer system 300, such as disk drive 334,
and loaded to
the main memory 312 during booting and/or initial operation of the computer
system 300.
In other embodiments, some or all of the software environment may be loaded
into the
main memory 312 by way of the NIC 338.
[0039] A description of the operation of the well log rendering program 410 in
accordance with the various embodiments, and in particular how operation of
the program
410 differs from related-art well log rendering systems, requires a brief
digression into
how the related-art systems render the curve 202. In particular, related-art
systems
render the well log values curve 202 based on a series of underlying
geometrical shapes
(i.e., underlying geometry), with the geometric shapes in most cases being
triangles
defined by vertices. The underlying geometry thus creates a wire-frame model
of the
curve for the well log values.
[0040] Figure 5 shows the underlying geometry of log 200 constructed as a
series of
triangles. In particular, the main processor 310 generates a series of
vertices 500 from
the underlying well log values. Each illustrative set of three vertices define
triangle. For
example, vertices 500A, 500B and 5000 define a triangle 502. Likewise,
vertices 500C,
500D and 500E define triangle 504. All the triangles taken together defines
the curve 202.
CA 02800183 2012-11-21
WO 2011/149460 PCT/US2010/036296
9
Once the main processor 310 generates some or all the vertices for a
particular set of well
log values, the main processor 310 sends some or all the vertices to the GPU
350.
[0041] Based on the vertices, the GPU 350 renders the curve 202 on the display
device
354. In some cases, the GPU merely colors the pixels within each triangle a
particular
color (e.g., blue), and colors the remaining background 506 a different color
(e.g., white)
such that the curve 202 is easily recognizable to the human eye. It is noted
that the
vertices shown in Figure 5, as well as the lines that define the triangles,
are not
necessarily visible in the final rendering. With respect to coloring, in other
cases (e.g.,
video games) the wire-frame structure created by the triangles may have a
"texture"
applied, where the texture may be thought of as a decal that is "pasted" onto
the
underlying wire frame. For example, the texture could be a brick pattern
pasted on to the
wire frame to give the appearance of the brick wall. The texture, if used, is
also provided
to the GPU 350 by the main processor 310. Based on the vertices, textures (if
any), and
various other pieces of information (e.g., "camera" position) provided by the
main
processor 310, the GPU 350 renders an image on the display device.
[0042] A particular set of well log values may comprise many thousands or
hundreds of
thousands of data points therein. In creating the vertices used to define the
curve of such
data points, many hundreds of thousands of vertices may be calculated by the
main
processor 310 and passed to the GPU 350. In many cases, the vertices used to
define
the curve for the entire set of well log values may be calculated and provided
to the GPU
350 by the main processor 310.
[0043] Defining the curve 202 in the manner illustrated by Figure 5 leads to
certainly
difficulties. For example, given the enormous amount of data used to represent
the curve,
the vertices that define the curve 202 for some well log values may require
more memory
than the capacity of memory 358 of the GPU 350. Relatedly, even if the GPU has
sufficient memory for vertices that define a curve 202 for particular set of
well log values,
there may not be sufficient capacity in the memory 358 for the main processor
310 to
provide vertices for multiple sets of well log values that the user would like
to view
simultaneously.
[0044] In accordance with the various embodiments, the curve 202 for a set of
well log
values is produced without using vertices to define the curve 202. More
particularly, in
accordance with the various embodiments the log 200 is created by the main
processor
CA 02800183 2012-11-21
WO 2011/149460 PCT/US2010/036296
310 sending to the GPU vertices that define a "panel." The main processor 310
also
sends well log values to the GPU 350, along with a program to be executed by
the
processor 356 of the GPU 350 which creates the curve 202 within the panel. The
entire
well log may thus be created by one or more panels stacked "end-to-end" with
the well log
values represented by a curve rendered within each panel. The discussion first
turns to
defining the panels.
[0045] In accordance with the various embodiments, each panel is defined by a
plurality
of vertices, and in some cases each panel is defined by four vertices. Figure
6 shows two
illustrative panels 600 and 602 for purposes of discussion. In particular,
panel 600 is
defined by four vertices 604, 606, 608 and 610. Likewise, panel 602 is defined
by four
vertices 608, 610, 612 and 614. While only two panels are shown in Figure 6,
any
number of panels may be used to construct an overall well log for a set of
well log values.
Moreover, while Figure 6 illustrates using four vertices to define each panel
with panels
being rectangular, other quadrilateral shapes, and shapes defined with more
than four
vertices, may be equivalently used. In the alternative, each illustrative set
of four vertices
may be considered to define two triangles stacked (in the view of Figure 6)
side-by-side.
[0046] In accordance with the various embodiments, the panels are indicative
of a path
of the wellbore from which the well log values were obtained. In the
illustrative case of
Figure 6, the underlying wellbore can be considered a vertical portion or non-
deviated
portion of a wellbore. Stated otherwise, the illustrative case of Figure 6
each the panel
may be considered to be indicative of the path of the underlying wellbore in
two
dimensions. However, the various embodiments are not limited to the two-
dimensional
path case, and are also applicable to wellbore paths in three dimensions.
[0047] Figure 7 shows a series of panels such that the panels are indicative
of a path of
the wellbore in three dimensions. In particular, Figure 7 shows a series of
panels which
are indicative of a portion of the wellbore 10 (Figure 1), and more
particularly still the
vertical portion 14 transitioning into the deviated portion 16. As
illustrated, the portions of
the wellbore are represented by five panels 700, 702, 704, 706, and 708. Panel
700 is
defined by four vertices 710, 712, 714 and 716. Likewise, panel 702 is defined
by four
vertices 714, 716, 718 and 720. A similar discussion may be made for the
remaining
panels being defined by vertices, many of which are shared between panels.
Having the
panels indicative of the path in three dimensions of the wellbore leads to the
illustrative
CA 02800183 2012-11-21
WO 2011/149460 PCT/US2010/036296
11
case where the panels are not rectangles when projected onto a two-dimensional
surface,
such as the paper on which Figure 7 is shown, or the panel of a display device
354. In
accordance with at least some embodiments, the main processor 310 creates the
vertices
for the one or more panels with vertices being points in any convenient two-
dimensional
or three-dimensional basis or space, such as the world geodetic coordinate
system.
[0048] Whether the log is to be shown as a two-dimensional log such as in
Figure 6, or a
three-dimensional log (projected onto two dimensions) such as in Figure 7,
once the main
processor 310 calculates some or all the vertices, the main processor 310
sends some or
all the vertices to the GPU 350. The GPU 350, in turn, creates the panels
based on the
vertices. It is noted, however, that the neither panels themselves, nor the
vertices, are
necessarily visible in the final rendering. A curve is rendered within or "on"
each panel
(discussed more below), and so while a panel may be distinguishable based on
the
boundaries of the curve or an outline of a selected background color, the
various
embodiments shall not require that each panel be specifically identifiable in
the final
rendering. The specification now turns how the main processor 310 provides the
well log
values to the GPU 350, and how the GPU 350 renders the curve within each
panel.
While such a discussion may be based on Figure 7, for convenience the
discussion is
based on Figure 6.
[0049] In accordance with various embodiments, the well log values for which a
curve is
to be created within a panel are communicated from the main processor 310 to
the GPU
350. Stated otherwise, in accordance with at least some embodiments the actual
well log
values themselves are communicated from the main processor 310 to the GPU 350.
Figure 6 shows an illustrative one-dimensional array of well log values 618
that may be
communicated to the CPU 350, and which one-dimensional array corresponds to
the
curve 202 in panel 600. The set of well log values 618 are illustrative of any
measured
parameter associated with the wellbore and/or surrounding formation. For
example, the
set of well log values 618 may be indicative of gas saturation of the
surrounding formation
as a function of depth.
[0050] In accordance with the embodiments illustrated in Figure 6, the main
processor
310 sends the well log values 618 alone, without any correlation of the well
log values 618
to depth. However, each set of well log values 618 is tied logically to a
particular panel,
and inasmuch as the panel 600 (defined by its vertices) is associated with a
depth within
CA 02800183 2012-11-21
WO 2011/149460 PCT/US2010/036296
12
the wellbore, the well log values 618 are correlated to depth (and assumed to
be equally
spaced). In other embodiments, the well log values 618 may be accompanied by
depth
values, particularly in cases where the assumption regarding equal spacing is
not valid.
[0051] While there may be many mechanisms by which to send the well log values
618
from the main processor 310 to the GPU 350, in accordance with at least some
embodiments the main processor 310 sends the well log values as "texture." In
stating
that the main processor 310 sends the well log values as a "texture", it
should be
understood that the well log values 618 are not a texture in the sense that
the well log
values define a texture (e.g., brick) that is to be applied to the panel;
rather, the main
processor 310 under OpenGLTM model is expected to send a texture file, and in
conformance with that expectation the well log values 618 are sent as a
texture file.
However, the GPU 350 does not accept and apply the texture file containing the
well log
values 318 as a texture or decal. Instead, the GPU 350 operates with the well
log values
618 to create the curve based on a progam, also provided by the main processor
310 to
the GPU 350.
[0052] The GPU 350 in this example discussion now has the vertices that define
panel
600 and well log values 618 (from which curve 202 will be constructed). In
accordance
with the various embodiments, the main processor 310 also sends an executable
program
620 to the GPU 350, where the program 620 defines how to create the curve 202
from the
well log values 618. In particular, the GPU 350 loads and executes the program
620 in
processor 356. The program 620, executed by processor 356, reads the well log
values
618 previously provided to the GPU 350 (e.g., reads the well log values 618
from the
memory 358 of the GPU 350), and creates the curve 202 within the panel 600.
The
process continues for each panel currently viewable on the display device 354,
with a
different set of well log values used for each panel. While the subset of well
log values
change for each panel, in some embodiments the same program 620 is used by the
GPU
350 to determine the curve within each panel. The discussion now turns to
illustrative
operational characteristics of the program 620.
[0053] In at least some embodiments, the program 620 creates a mathematical
model
for the curve to fit within the panel. In particular, the program 620
determines a scale of
the horizontal size of the panels. In some embodiments, the program 620 reads
well log
values over the entire log (i.e., reads all the well log values sent by the
main processor
CA 02800183 2012-11-21
WO 2011/149460 PCT/US2010/036296
13
310, in some cases across multiple "texture" files), determines the maximum
and
minimum values, and from the maximum and minimum values determines the scale
represented by the horizontal size the panels. In other embodiments,
particularly
embodiments where the main processor 310 does not provide all the well log
values to
the GPU 350, the main processor 310 sends an indication of the horizontal
scale (e.g.,
sends an indication within each "texture" file, or sends the horizontal scale
a single time
as a "texture" file).
[0054] Regardless of the precise mechanism by which the program 620 determines
the
horizontal scale, the program 620 then maps the well log values into the
panel. For
example, each well log value for a particular panel may be assigned a point in
the world
geodetic coordinate system within the panel, with the "horizontal" location of
the point
based on the horizontal scale and the particular well log value, and the
"depth" location of
the point based on the assumed depth (if the well log values are assumed to be
equally
spaced) or the actual depth if provided by the main processor 310. The well
log values
are not continuous, and thus in some embodiments the "space" or distance
between two
points representing the well log values in the panel may be logically spanned
by a straight
line. Stated otherwise, the value of the mathematical model between well log
values is
determined by straight-line or linear interpolation. Thus, in some
embodiments, the
program 620 makes a piece-wise linear curve 202, as illustrated in Figures 2
and 6.
[0055] The program 620 then selects colors for each pixel of the panel based
on the
pixel's location relative to the curve of the mathematical model. For example,
consider a
series of abutting pixels residing on a horizontal row at location 622. In an
example
implementation, the program 620 may select a left-most pixel, and compare the
location
of the pixel to the mathematical model of the curve. The first pixel may
reside to the left of
the mathematical model of the curve 202, and thus may be illuminated with a
fill color
(e.g., white). The process is repeated for each pixel in the horizontal row,
and is repeated
for each row in the panel. When a pixel is analyzed that resides on or to the
right of the
mathematical model, the pixel's color may be selected to be the color of the
log (e.g.,
blue) to distinguish the curve from the fill color. Pixels of the display that
reside outside
the one or more panels are applied a background color (e.g., black). When
completed, the
curve will be evident, in this example, as the boundary between the background
color (left
side of curve 202) against the curve color (right side of curve 202). Using
white as a fill
CA 02800183 2012-11-21
WO 2011/149460 PCT/US2010/036296
14
color, blue to delineate the curve 202, and black as the background color is
merely
illustrative, and any color scheme may be equivalently used.
[0056] Several points are in order before proceeding. First, creating the
curve 202 in the
manner described, the underlying geometry for the curve 202 is not represented
by
vertices defining geometric shapes. Rather, the curve 202 is determined and
rendered
based on a pixel's location relative the boundary of the mathematical model.
Thus, the
amount of memory and extent of processing by the GPU 350 to render the
illustrative
panel 600 is significantly less than if the curve 202 was defined by
underlying geometry.
Further, in the example curve 202 of Figures 2 and 6, the curve 202 is a piece-
wise linear
curve 202, with "straight line" interpolated values between specific values.
Thus, the
mathematical model for the curve may be a series of points in the space or
basis as
determined by the GPU 350 based on the specific well log values. When
determining the
color of a particular pixel that resides between representations of specific
well log values,
the program 620 may perform the linear interpolation on-the-fly. In other
embodiments,
the program 620 may perform the interpolation in advance, such that selecting
a color for
a pixel is merely a comparison of the pixels effective location in space to
the mathematical
model.
[0057] At sufficiently low resolution (i.e., viewing position of the curve
sufficiently far
"back"), the curve 202 may look smooth, particularly if there are a large
number of well log
values displayed within the panel. However, as the view moves closer (stated
otherwise,
as magnification increases), the piece-wise linear aspect of the curve 202 may
become
more apparent. In some cases, the piece-wise linear aspect at high
magnification may be
undesirable, and other embodiments address the undesirability of the piece-
wise linear
curve using program 620.
[0058] In accordance with at least some embodiments, the mathematical model of
the
curve used to determine a color applied to each pixel within a panel is a more
smoothly
varying function between specific well log values than the straight-line or
linear
interpolation discussed above. Stated otherwise, the curve produced within a
panel is a
more smoothly varying curve, to the extent the resolution of the display
device will allow,
and as opposed to piece-wise linear. In order to smoothly vary the curve, the
program
620 in accordance with these embodiments calculates a smoothly varying
mathematical
model of the curve associated with the well log values. In accordance with at
least some
CA 02800183 2012-11-21
WO 2011/149460 PCT/US2010/036296
embodiments, the program 620 determines the mathematical model by first
determining
the points in space that correspond to the well log values as described above,
and then
calculate values between the points in space that correspond to the well log
values by an
interpolation method that produces smoothly varying changes, such as cubic
interpolation, cosine interpolation, Hermite interpolation.
[0059] Figure 8 shows a panel 800 to illustrate the smoothing of the curve 802
in
accordance with particular embodiments. In particular, the smoothly varying
curve 802 of
Figure 8 is made of an illustrative six well log values 804, 808, 810, 812 and
816. The
straight line interpolation between the points is illustrated in Figure 8 as
dashed line 818.
However, in the particular embodiment the values between the points
representative of
well log values are determined based on a cubic interpolation, leading to a
smooth curve
802. Table 1 below shows an illustrative software routine in pseudo-code
(roughly
equivalent to the C programming language) which may be used to calculate the
value
between the points 804, 808, 810, 812 and 816.
double Cubiclnterpolate (double a0, double al, double
a2, double a3, double tt){
double A, B, C, D, E, F, c1, c2;
tt2 = tt*tt;
A=(a0+a2-2*a1)*0.5;
B=(a2-a0)*0.5;
C=al;
D=(a1 +a3-2*a2)*0.5;
E=(4*a2-3*a2-a3)*0.5;
F=a1;
c1=A*tt2+Btt+C;
c2=D*tt2+e*tt+F;
return(c1 *(1-tt)+c2*tt);
TABLE 1
Five parameters are passed to the illustrative routine each time the routine
is called, the
five parameters being four data points representative of four consecutive well
log values
(i.e., a0, a1, a2 and a3, being in double precision), and tt being a value
between 0 and 1
representing an increasing incremental "distance" between points a1 and a2 on
each call.
The illustrative routine returns a single double precision value representing
a cubic
interpolated value between points al and a2. The routine is called multiple
times (with
differing values of tt, but with same values of a0, al, a2 and a3) to
interpolate the points
between al and a2. When interpolating between the next set of data points,
three of the
CA 02800183 2012-11-21
WO 2011/149460 PCT/US2010/036296
16
previous data point, along with the next consecutive data point, are passed as
a0, al, a2
and a3. Stated otherwise, cubic interpolation uses four data points to make
the
interpolation between the center two data points. As before, the program 620
may use
the illustrative software routine from Table 1 to interpolate on-the-fly when
selecting pixel
colors, or the program 620 may use the illustrative software routine to
determine all the
points between points prior to the determination of pixel colors in a panel.
[0060] The various embodiments discussed to this point assume that a single
curve is
created in each panel. However, in accordance with other embodiments, multiple
logs
may be displayed in a fast and efficient manner. In particular, and
considering a single
panel with the understanding a log is made of a plurality of consecutive
panels, in
accordance with a particular embodiment the main processor 310 passes to the
GPU 350
vertices for the panel along with multiple sets of well log values (either as
single multi-
dimensional "texture" file, or perhaps multiple "texture" files), and a
program 620 having
the capability to render multiple curves in a panel. The GPU 350, executing
the program
620, co-renders the curves in the same fashion as discussed above (i.e.,
without creating
underlying geometry). Figure 9 shows an illustrative panel 900 having two
curves 902
and 904 therein. Curve 902 is shown with a solid line and represents a first
set of well log
values, and curve 904 is shown with a dashed line and represents a second set
of well
log values. Rendering the curves involves a determination by program 620
regarding
each pixel that falls within the panel 900.
[0061] In particular, the program 620 in these embodiments makes a
mathematical
model for each curve 902 and 904 within the panel (e.g., straight line
interpolation, cubic
interpolation). The program 620 then selects colors for each pixel of the
panel based on
the pixel's location relative to the mathematical models. For example,
consider a series of
abutting pixels residing on a horizontal row at location 906. In an example
implementation, the program 620 may select a left-most pixel, and compare the
location
of the pixel to the mathematical models of the curves. The first pixel may
reside to the left
of both mathematical models, and thus may be illuminated with a fill color
(e.g., white).
The process is repeated for each pixel in the horizontal row (in this example
moving left to
right). When a pixel is analyzed that resides on or to the right of the
mathematical model
for curve 902, but to the left of the mathematical mode for curve 904 (the
region shaded
upper right to lower left), the pixel's color may be selected to be a first
color (e.g., green).
CA 02800183 2012-11-21
WO 2011/149460 PCT/US2010/036296
17
When a pixel is analyzed that resides on or to the right of the mathematical
model for
curve 902, and on or to the right of the mathematical model for curve 904 (the
region
shaded upper left to lower right), the pixel's color may be selected to be a
second color
(e.g., blue). The process is repeated for each pixel in the horizontal row,
and is repeated
for each row within the panel. Pixels of the display that reside outside the
one or more
panels are applied a background color (e.g., black). When completed, the
multiple curves
will be evident, and also the relative relationship between the multiple
curves. Using white
as a fill color, green and blue to delineate the curves, and black as the
background color
is merely illustrative, and any color scheme may be equivalently used.
[0062] While the discussion with to Figure 9 assumes each set of well log
values have a
somewhat large range of possible values, well log values may convey
information by way
of a set of Boolean values. That is, the well log values sent for the second
curve could be
Boolean values (i.e., zero or one), or another set of predetermined values, to
convey
information as to the congruence of the first set of well log values and
another parameter.
For example, the first set of well log values could convey information
regarding the ratio of
carbon and oxygen sensed in the surrounding formation as a function of depth,
while a
second set of well log values could identify the presence or absence of a
particular
formation lithology (e.g., shale). Figure 10 shows an illustrative panel 1000
having two
curves 1002 and 1004 therein. Curve 1002 is shown as a solid line and
represents in this
example a first set of well log values (e.g., ratio of carbon and oxygen), and
curve 1004 is
shown as a dashed line and represents a second set of well log values (e.g.,
formation
litholgoy). In the illustrative case of Figure 10, areas where the curve 1004
is "off", a first
color or texture is plotted to show the curve 1002 (the first color or texture
shown by
shading upper left to lower right), and in areas where the curves overlap a
second color or
texture is plotted (shown by shading upper right to lower left). Figure 10
further shows
that when a set of well log values are rendered in an on/off sense, when "on"
the curve
representing the well log values may use values from another set of well log
values so as
to track together when "on". In other embodiments, the on/off set of well log
values may
extend across the entire panel when "on". Regardless of the precise mechanism
for
showing the sets of well log values, by rendering the multiple sets of well
log values as in
Figure 10, the congruence of well log values is easily identifiable to the
human eye.
CA 02800183 2012-11-21
WO 2011/149460 PCT/US2010/036296
18
[0063] Here again, in the illustrative case of two or more sets of well log
values, the
curves in each panel are rendered based effectively the vertices used to
define only the
panel itself, and thus amount of memory 358 and computation cycles of the
processor
356 to produce the co-rendered curves is significantly less than in situations
where the
each curve is defined by underlying geometry. Further, while only discussed
with respect
to a single panel, multiple panels are be stacked end-to-end to create the
overall log.
[0064] The various embodiments discussed to this point have assumed a single
frame
on the display device 354 showing one or more panels that simulate the
trajectory of the
wellbore from a particular viewing position, and which show the one or more
curves in
each panel. However, the various embodiments also contemplate animating on the
display device 354 movement of the viewing position relative to the panels. In
particular,
the main processor 310 may receive from the viewer or user an indication of a
direction to
move the display shown in relation to the trajectory (e.g., the indication of
the direction t0
move may be received by game controller 346 joystick movement or the keyboard
342).
The main processor 310 thus sends a series of viewing position indications to
the GPU
350, with the GPU 350 generating an updated two-dimensional projection (a
frame
update) based on each in the series of viewing position indications. For
smooth animation
between a starting point and ending point, the main processer 310 should send
at least
twenty different viewing positions a second, and likewise the GPU 350 updates
the two-
dimensional projection at least twenty times a second. Faster frame rates
provide visually
smoother movement "through" the scene.
[0065] Figure 11 shows a method in accordance with at least some embodiments.
In
particular, the method starts (block 1100) and comprises: sending to a GPU of
a computer
system vertices that define a panel, the sending by a main processor of the
computer
system, the main processor distinct from the GPU (block 1102); sending a
program to the
GPU, the sending of the program by the main processor (block 1104); sending a
first set
of well log values to the GPU, the sending of the first set of well log values
by the main
processor (block 1106); executing the program by the GPU which program
determines a
first curve from the first set of well log values by the program executed by
the GPU (block
1108); and displaying on a display device of the computer system the first
curve within the
panel (block 1110). Thereafter, the illustrative method ends (block 1112).
CA 02800183 2012-11-21
WO 2011/149460 PCT/US2010/036296
19
[0066] The well log rendering program 410, executed on the main processor 310,
merely passes the curve program 620 to the GPU 350. The program 620 passed is
not
created by well log rendering program 410; rather, the program 620 is created
by a
programmer in advanced and stored on a memory of the computer system (e.g.,
disk
drive 334). However, in an overall system that has the ability to perform the
smoothing of
the curves based on the type of interpolation selected by a user, the well log
rendering
program 410 may selected from multiple versions of program 620 to send to the
GPU 350
for the desired case. Moreover, other display-type calculations may be
performed by the
GPU 350, but have not been discussed so as not to unduly complicate the
discussion.
For example, the GPU 350 may also perform lighting calculations such as
diffuse lighting,
ambient lighting and specular lighting, in addition to the calculations to
arrive at the
rendered curves.
[0067] From the description provided herein, those skilled in the art are
readily able to
combine software created as described with appropriate general-purpose or
special-
purpose computer hardware (e.g., graphics processing unit) to create a
computer system
and/or computer subcomponents in accordance with the various embodiments, to
create
a computer system and/or computer subcomponents for carrying out the methods
of the
various embodiments, and/or to create a non-transitory computer-readable
storage media
for storing a software program to implement the method aspects of the various
embodiments.
[0068] The above discussion is meant to be illustrative of the principles and
various
embodiments of the present invention. Numerous variations and modifications
will
become apparent to those skilled in the art once the above disclosure is fully
appreciated.
It is intended that the following claims be interpreted to embrace all such
variations and
modifications.
